Ancillary (or spectator) ligand-metal coordination complexes (e.g., organometallic complexes) and compositions are useful as catalysts, additives, stoichiometric reagents, monomers, solid state precursors, therapeutic reagents and drugs. Ancillary ligand-metal coordination complexes of this type can be prepared by combining an ancillary ligand with a suitable metal compound or metal precursor in a suitable solvent at a suitable temperature. The ancillary ligand contains functional groups that bind to the metal center(s), remain associated with the metal center(s), and therefore provide an opportunity to modify the steric, electronic and chemical properties of the active metal center(s) of the complex.
Certain known ancillary ligand-metal complexes and compositions are catalysts for reactions such as oxidation, reduction, hydrogenation, hydrosilylation, hydrocyanation, hydroformylation, polymerization, carbonylation, isomerization, metathesis, carbon-hydrogen activation, carbon-halogen activation, cross-coupling, Friedel-Crafts acylation and alkylation, hydration, dimerization, trimerization, oligomerization, Diels-Alder reactions and other transformations.
One example of the use of these types of ancillary ligand-metal complexes and compositions is in the field of homogeneous catalysis to form a sp.sup.2 C--N bond. A sp.sup.2 C--N bond is a structural component in a variety of synthetic and naturally occurring biologically active compounds, polymers and dyes. Currently, existing methodologies are not general, in that different complexes or compositions are used for different substrates. Also, existing ligands are expensive. Thus there is a need for new, less expensive ligands that are generally applicable to all types of C--N bond formation, including sp.sup.2 C--N bond formation.
Moreover, it is always a desire to discover new ancillary ligands, which upon coordination to a metal center will catalyze reactions differently from known ligand systems. This invention provides new ancillary ligands that may be used for coordination to a metal center or included in a composition with a metal or metal precursor compound. Upon coordination to the metal center or inclusion in the composition, such ligands influence the electronic and steric environment of the resulting coordination complex and may catalyze reactions differently, including more efficiently and selectively than known systems.